Mongol Siege and Sack of Baghdad

Hulagu Khan, a grandson of Genghis Khan, besieged Baghdad in January 1258 CE. The city fell on 10 February 1258, and the Mongols sacked it. The last Abbasid caliph, al-Musta'sim, was executed. Sources give very large numbers of dead, which historians consider uncertain. Later accounts also describe the destruction of libraries. A branch of the Abbasid family later continued in Cairo under Mamluk protection.